In general, a stereoscopic display device is of a binocular type in which the respective images from the left and right visual points (hereinafter, binocular-parallax images) are presented to the left and right eyes of an observer. A stereoscopic display device of such a type makes it possible to obtain a stereoscopic image by displaying a plurality of binocular-parallax images and recomposing them. As a method of presenting the respective binocular-parallax images to the left and right eyes of an observer in a stereoscopic display device of a binocular type, for example a method of using a pair of eyeglasses such as special polarizing glasses or shutter glasses is mentioned. Lenticular type, parallax stereogram type and similar methods are examples of methods that do not employ the use of glasses.
And there is a stereoscopic display device using an integral photography method (hereinafter, an IP method for short) that is proposed up to now in a field of photography. For example, an IP method stereoscopic display device has a display panel for displaying multiple planar images obtained by viewing a target stereoscopic image from different directions and a light control panel of non-transmissibility that is located on the front face (viewing side) of the display panel and formed so as to enable viewing of the images on the display panel through a light transmitting portion.
As an example of an IP method stereoscopic display device, there is a method that synchronously performs updating of the planar images on the display panel and control of the transmissibility of a light transmitting portion of the light control panel (see Patent Document 1 for example). In such a method, light transmitting portions that are usually non-transmissible are made selectively transmissible sequentially and planar images corresponding to the light transmitting portions made transmissible are displayed properly on the display panel. In such a way, viewing all planar images updated and sequentially displayed within an afterimage retaining time of eye enables a desired stereoscopic image as a whole to be viewed.
Here, in particular such a method is called a multiplex pinhole scanning type integral photography method (hereinafter, an MPS-IP method for short). According to the MPS-IP method, since light transmitting portions are made transmissible sequentially and planar images are updated synchronously, planar images observable from one light transmitting portion increase. Therefore, the resolution is improved compared with a conventional IP method in which a light transmitting portion does not change usually in transmittance.
Patent Document 1: Japanese Patent Laid-Open Publication No. H6-160770